Physics 320
Astrophysics I:  Lecture #3 HW Problem
Prof. Dale E. Gary

Imaging the Solar Eclipse

Prob. 3.1: In Lecture 3, we gave the equation for plate scale, and an example of how to calculate the linear size of an object at the focal plane of a telescope. For the 2017 August 21 total solar eclipse, I used an 80 mm f/6 telescope and the ZWO ASI120 camera, whose specifications are listed in the table below. (Use the fact that 1 degree = 60 arcmin = 3600 arcsec.)

a. What is the plate scale (in mm/degree) for this telescope?

b. What is the angular size, in arcsec, that one pixel of this camera would represent?

c. What is the field of view of the camera, horizontally and vertically, in arcminutes?

d. Will the Sun (angular size 1/2 degree) fit in the camera frame horizontally? Vertically?

Model Number ASI120MC-S
Color or Monochrome Camera? Color
Imaging Camera Series ZWO ASI120
Sensor Model AR0130CS
Sensor Type CMOS
Pixel Size (µm) 3.5 x 3.5
Pixel Array (pixels) 1280 x 960
Camera Cooling Natural Convection
CCD Architecture Frame Transfer
Bit Depth 12-Bit
Minimum Exposure 64 microsecond
Maximum Exposure 1000 seconds
Software Included Windows Camera Driver, ASCOM Driver, SharpCap, FireCapture, Stakkert 2
Computer Interface USB 3.0
Includes Filter Wheel? No, Sold Separately
Camera Dimensions 2.44 x 1.1 inch
Camera Weight (lb.) 0.22
Camera Warranty 1 year